Grateful for the details about the differences between personalities, traits, etc in Sims3 and Sims4...and learned something new! Didn't know there were such things as "Forbidden words" in Sims4, or that coffin woohoo was a thing (must be a Vampires thing, and I don't have that).
It is true that the tendency of moodlets to override and obliterate all else, can be unsettling. Going from the depths of grief to Happy and Energized while the Grief plays on in the background as a blue bar, but doesn't appear to affect them right then, is weird. Having an enraged husband of a cheating spouse go from Ranting to smiling and chatting at the table in an instant, while his outrage lives quietly on, but somehow suppressed enough that he can act the image of courtesy, is weird.
I do think a lot of what makes Sims4 characters so potentially tantalizing to me, is what is hidden from me, but I keep picking up on. I call it Hidden Architecture, but can only surmise its existence from noticing that some couples have chemistry and some don't, even if I make them do all the interactions to make a romance work...it will work superficially, and even their woohoo isn't as good. When the compatibility isn't there, they don't seek out each other's company in odd moments, or initiate romance, or much of anything, together.
Some Sims seem to have more initiative than others toward self-care. I actually had one that earned the No Excuse award for wetting himself in a lot with 5 toilets. He never did anything for himself, and I got tired of micromanaging him, so I deleted him, no regrets. Other Sims seem to vary in how quickly or effectively they respond to their own needs, or the needs of their babies (some will even respond to any baby, without prompting, and without being made to by selecting certain traits. I think those will make superb parents or nannies)
So, far less is up to us, and yes, moodlets and objects give us the ability to overcome a lot of things. That does flatten the game a bit. But I still love the surprises I keep running into with some Sims having such individual tendencies, that weren't made by me.